This standard specifies the type, size and technical conditions of signs. This standard is applicable to product nameplates, operation indication plates, instruction plates, circuit schematic plates, design data chart plates and safety sign plates (collectively referred to as signs) for various electromechanical equipment, instruments and meters and various components. The types and dimensions of this standard are not applicable to panels, dials, trademarks and art decoration plates of instruments, meters and household appliances. Some of the above products can be used for reference in terms of technical conditions.